Horsepower at offroad

I have always wondered why sometimes off road trucks and vehicles have very high horsepower engines. I have seen that in reality and also in BeamNG offroad vehicles are quite high in horsepower.

Maybe it is mud where that horsepower is needed? However in BeamNG I haven't found much need for high horsepower, but perhaps official offroad vehicles have some planned use case scenarios which I'm unaware of, I would like to know bit more about those and background of why it is chosen to have such high horsepower motors in those setups, I believe there is something new for me to learn here.

I did test Roamer and Pickup with close to identical setups, but in pickup I had I6 while Roamer had that powerful offroad config motor, there was not much of difference what I could tell in my usage:


Someone is soon asking, so map is Crawl Central, only offroad map that I know which fits perfectly for my kind of offroading. D-Up and more D-series parts mods provide some parts to vehicles so that they are actually capable of handling that terrain.

I'm interested to test Hopper with 1.3L Suzuki motor next, somehow I think power need with low range is really really small, so it might do just fine with that 5X hp? However there must be some bit of information I don't have because it is so common to have lot of power in these vehicles, educate me, what I don't know here?

 

It's probably for the torque as well. If I had to guess, the offroad configs also get a lot of power because they can also be used on maps like Utah where there is a fair amount of dirt roads that can be raced on.

 

I make my off-roaders by not making them so fast like they are stock. (on off-road vehicles, there's a gear range to where it makes you go high and low, but i prefer to make my custom transmission) And i make the speed of the vehicle very low, giving it much more power. the "special" transmission has 2 gears, which for me gives me a way better off-roading experience. I've never been stuck with this off-roader i built, it has never got stuck inside the mud (i have the Taza off-road parts, so with the tires that pack provides, it makes the truck even better)

But it's WAY Top-heavy, so it tips over very easily.

 

Unless you are building a rock bouncer or mud truck (where wheel speed > torque), a low horsepower engine is fine. Low gearing is much more important for a rock crawler because the low-end torque is what you want. In real life, low gearing also helps in the sense that less wheel speed leads to less stress on parts so you are less likely to break axle shafts, gears, and driveshafts.

 

I did Suzuki F10A (That is in Samurai SJ410, I guess it was Jimny in US) with it's mighty 44hp for a Hopper, it shows in game 38hp, with crawler box it actually works somewhat ok, not too much of power though! Boring video proof:

Sadly I could not find torque curve, so made mostly guesswork torque curve, max torque and hp was only that I found. Hopper is just bit annoying that it fells over constantly, probably my driving is at fault.


Also I find less power to provide easier control, with game pad throttle range is rather limited, for transmissions I'm using automatic, it is bit worse than manual when descending, but really nice when climbing.


What I'm thinking is that dev team has some plans for these high power offroad vehicles, maybe some missions that are still secrets? I think that there are many cars that are not used much in content yet, there might be more of games/campaign/such content coming when Beam is more mature, surely they could have some plans for offroad Roamer too which we haven't heard anything yet?

Update, I did add F10A engine file that has also torque converter and autobox adjusted to that engine if someone wants to try such, that needs to be in Documents\BeamNG.drive\vehicles\hopper to work and you need to select F10A parts from parts selector (engine, transmission and torque converter) use crawler transfer box and it should work somewhat. It is not very refined, just a quick test, but probably lowest power motor for Hopper.

Update2, I don't know much of mud pits in BeamNG, except grid map, I think horse power demands become clear here, however if going slow truck will not get stuck which kind of disqualifies point of having high HP setup, but that might of course change in future too:

 

Basically going off what you already discovered and what has already been said, power in the off-roading world is pretty much nothing but a useless statistic. Usually the reason that power is bumped up is because of the fact that when someone does a lift on there truck and puts bigger tires on it, usually they do not end up changing the gearing. This in turn makes it harder for the engine to turn the wheels and the usual solution is to just add more power. Seems silly, but I know a lot of people that do exactly that in real life... seriously.

As far as how little power you need... if you have RPM's and gearing... you can make enough torque to move just about anything with just about anything... no joke... check this thing out here.

 

someone needs to make that
just a d series frame with a seat and a tiny engine

 

I would honestly love to drive that around.

 

I would make it but I have too many projects right now

 

Hmm, 1/5 is 20%, you got 20 times more power, maybe there is a rule?

I think I had bit over 600hp in that mudding video, you can actually see difference in mud physics when wheel speed starts to be that high, handling becomes very different, if it would be easier to stuck when going slow in mud, then it might make offroading even richer experience in BeamNG.

I haven't tested that only mud pit I know with 38hp Hopper, it might get stuck actually!

Testing these things makes you appreciate ground physics of BeamNG quite a lot.

 

Well, I saw up above that you had trouble with coming up with a torque curve... if you want to try specific engine's, I can generate a torque curve (very generic one) for you if you give me the Bore, Stroke, and HP (or KW) of whatever engine you want to have a torque curve of... I can also figure out the proper final drive ratio if I know the weight and size of the tires.

 

I could only find HP and torque official ratings for little Suzuki motor, so had to estimate shape of the curve, which is not too much of trouble, but I really would like to see real torque curve, as all those odd dips in curve make motor to have little bit of more character than what we can synthetically create.

Torque curve of engine rarely is smooth steadily rising one, at some rpm cylinders get better fill and swirl, which leads to boost in torque, on some rpm there is opposite situation true, that is why I would like to see real torque curves and preferably very little smoothing if possible.

Wikipedia claims:
F10A — 1.0 L (970 cc/59 cu in, 65.5 x 72.0 mm)

This site claims https://www.ultimatespecs.com/car-specs/Suzuki/568/Suzuki-SJ-410-.html
Maximum power - Output - Horsepower :
45 PS or 44 bhp or 33 kW @ 5500 rpm

Maximum torque : 74 Nm or 54 lb.ft @ 3000 rpm

Of course when BeamNG is input correct values, then some losses are applied and torque curve app shows little less power, but torque curve app should be crank power, so I guess input must be compensated to get real figures, which is bit annoying, even more annoying it becomes when building turbo setups as you have to play with quite many variables and change in file is not change you get at the end. I haven't found any better way than keep adjusting value by value, tiny bit by tiny bit, checking with torque curve app and re-adjusting until curve is perfectly matching to dyno data.

Naturally if dyno data is wheel power one has to estimate drivetrain losses, but only in case where dyno sheet is not corrected to flywheel power.

It is quite boring and takes very long time with turbo engines, NA engines are quite simple in that regard as there are no spooling etc. to consider.

Would be handy if you would input numbers of torque curve and that would be what you get at max boost, then less boost would decrease the values instead of increasing, but it is never that simple.

I can't get Hopper to weight only 860kg, but when I made it to be just a frame, motor and axles, little motor with manual box and crawler transfer case was just fine, that 6.5hp thing posted earlier might also work if gearing is adjusted, but I'm not sure how well BeamNG will cope with very small amount of power, might need to adjust friction values.


Torque curve app does not like to scale into really small values though. Need to play with this when I have time, I don't think that small power has been explored very extensively in BeamNG yet.

 

Yeah, unfortunately, my Engine calculator isn't quite on the level of detail that you would like it to be at yet. I don't have all the subtle nuances of differing swirls at different RPM's, intake runner lengths, cam timings, ignition timmings, header tube lengths or any of that calculated yet... I have a lot, but not that much. Currently, my little simulation takes into account bore, stroke, compression ratio, piston type (for mean piston speed), number of strokes, number of pistons, intake and exhaust efficiency (overall, not at multiple RPM's), amount of boost, and the efficiency of how the boost is created. Plus side is its very accurate when it comes to raw calculated numbers... the downside is the fact that it does produce a smooth arking torque curve that doesn't have all the subtle nuances in additional torque that is created at specific RPM's for varying reasons. I am working on a new calculation that should be able to take all of that into account, its just... I haven't quite figured it out yet.

 

It might be kinda hard to do, what I have found out is that you can get only starting point even with a best tools, at the end each bin has to be then adjusted individually to match real world data. I don't know if you remember that tool I gave you link in some 10 months ago, which had different head flows, cams etc. which then generated torque curve?

Lack of radiator does have some setbacks, but it does work quite long time without it, climbs well too. Maybe need to mod radiator into that thing *scratches head*:

 

Yup, I remember them... well... I didn't until you mentioned it... but I do now that you did. As for the lack of radiator... is it possible to set the engine up to be air cooled? with this low amount of power, air cooling should be more than enough and I think air cooling is a thing that is in the game now. (I think)

 

Oh, air cooling is possible now? Didn't know that, thanks, it will make things bit easier, even it is a bit of cheat as original motor was not air cooled, but for testing purposes this is just fine.

Attached is air cooled latest version.